This invention relates generally to a vehicle door latch and more particularly to a vehicle door latch that has a forkbolt, a detent for holding the forkbolt in a latched position and a release mechanism for moving the detent to a position releasing the forkbolt.
An automotive closure, such as a door for an automobile passenger compartment, is hinged to swing between open and closed positions and conventionally includes a door latch that is housed between inner and outer panels of the door. The door latch functions in a well known manner to latch the door when it is closed and to lock the door in the closed position or to unlock and unlatch the door so that the door can be opened manually.
U.S. Pat. No. 6,053,543 granted to Frank Joseph Arabia et al Apr. 25, 2000, which is hereby incorporated by reference, discloses a vehicle door latch that has a forkbolt and a spring biased detent that holds the forkbolt in a latched position. The spring biased detent is moved by a manually operated release mechanism that includes an intermittent lever that operates on a pin that is attached to the detent. The lower end of the intermittent lever is pivotally attached to one end of an inside unlatching lever by a pivot pin. The other end of the inside unlatching lever has a generally perpendicular tab that is used for operating the unlatching lever by an inside door handle or the like. When the inside door handle or its equivalent rotates the unlatching lever, the intermittent lever is pulled down moving the pin and detent to a release position where the fork bolt is released allowing the vehicle door to be opened from inside the vehicle.
The release mechanism of the door latch also includes an outside release lever or unlatching lever. One end of the outside unlatching lever is pivotally mounted on a stud while the opposite end of the outside unlatching lever is adapted for operating the outside unlatching lever by an outside handle or the like. When the outside handle or its equivalent rotates the outside unlatching lever, the unlatching lever engages the pin attached to the intermittent lever and pulls the intermittent lever down moving the detent to a release position where the fork bolt is released allowing the vehicle door to be opened from outside the vehicle.
The door latch also includes an independent lock mechanism that includes the intermittent lever and that is preferably power operated. The lock mechanism has a compound lock lever and an inside lock lever and an outside lock lever that operate the compound lock lever. The compound lock lever locks the door latch by moving the intermittent lever to a disabling position where the intermittent lever does not move the detent when it is pulled down by the release mechanism. The door latch also includes an optional power operated double lock mechanism.
The door latch disclosed in the Arabia ""543 patent is suitable for its intended purpose. Moreover, the door latch of the Arabia ""543 patent is typical of the conventional approach of having a mechanically operated release mechanism and an independent lock mechanism that may or may not be power operated.
The vehicle door latch of the invention has a power operated release mechanism rather than a mechanically operated release mechanism that is typical of the prior art. The power operated release mechanism eliminates the need for an independent lock mechanism since the vehicle door latch is locked simply by cutting off power to the power operated release mechanism. The vehicle door latch of the invention preferably includes a mechanical override to unlatch the vehicle door latch in the event of a power failure.
Objects, features and advantages of the invention will become apparent from the description below, which is given by way of example with reference to the accompanying drawings.